RT Journal Article
SR Electronic
T1 Potassium-stimulated purine release by cultured sympathetic neurons
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 1680
OP 1687
DO 10.1523/JNEUROSCI.05-07-01680.1985
VO 5
IS 7
A1 EJ Wolinsky
A1 PH Patterson
YR 1985
UL http://www.jneurosci.org/content/5/7/1680.abstract
AB Environmental factors can influence cultured sympathetic neurons to acquire several different neurotransmitter phenotypes. Cholinergic and noradrenergic transmitter status can be influenced by heart cell conditioned medium, chronic depolarization (Patterson, P. H. (1978) Annu. Rev. Neurosci. 1:1–17), and rat serum (Wolinsky, E. J., and P. H. Patterson, (1985) J. Neurosci. 5:1509–1512); formation of electrical synapses can be induced by insulin (Wolinsky, E. J., H. Patterson, and A. L. Willard (1985) J. Neurosci., 5:1675–1679). Purine release has also been proposed as a possible transmission mode for sympathetic neurons (Potter, D. D., E. J. Furshpan, and S. C. Landis (1983) Fred. Proc. 42:1626–1632), and as such, it is another candidate for environmental modulation. In this report, we assess the ability of sympathetic neuron cultures grown with and without serum to release metabolically labeled tritriated purine compounds in response to depolarization. Exposure to 54 mM potassium stimulated release of adenosine, inosine, and hypoxanthine from both serum-supplemented and defined-medium cultures. However, depolarization-stimulated release of adenine nucleotides was observed only from serum-supplemented cultures and not from serum-free cultures. The release of adenine nucleotides from serum-containing cultures is affected by divalent cations in the manner expected for a neurosecretory process. The failure of serum-free cultures to release detectable adenine nucleotides raises the possibility that they do not share with, or that they differ from, serum-supplemented cultures in the purinergic aspect of the multiple transmission modes available to sympathetic neurons, and that this difference may be due to effects of the culture medium.